I think tech companies would've eventually attempted to build some walls around that and monetise it. Regardless of technology, the challenge is someone wants to "take this to the next level" - as long as it's investor driven, it remains "open" only as long as that brings more money or community good will
And there is Steam on Desktop. You buy a game once you can play it on every platform with Steam which is all the platforms. If you buy a game in the App Store, you're stuck to places Apple likes.
I work for a product agency, and the ability to rely on Safari has unlocked many possibilities for us. It's significantly easier to create a unique and beautiful experience (web or native) for iOS than it is for Android. This is further facilitated by the consistency and performance of the iPhone platform itself.
> highlights the risks associated with the centralization of instant messaging services
Any cervices, really